scholarly journals Evaluation of Physical Properties of a Metakaolin-Based Alkali-Activated Binder Containing Waste Foam Glass

Materials ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 5458
Author(s):  
Petra Mácová ◽  
Konstantinos Sotiriadis ◽  
Zuzana Slížková ◽  
Petr Šašek ◽  
Michal Řehoř ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Physical Properties ◽  
Foam Glass ◽  
Glass Production ◽  
Alkali Activation ◽  
Activation Process ◽  
X Ray ◽  
Thermal Insulating ◽  
The Matrix ◽  
Alkali Activated

Foam glass production process redounds to large quantities of waste that, if not recycled, are stockpiled in the environment. In this work, increasing amounts of waste foam glass were used to produce metakaolin-based alkali-activated composites. Phase composition and morphology were investigated by means of X-ray powder diffraction, Fourier-transform infrared spectroscopy and scanning electron microscopy. Subsequently, the physical properties of the materials (density, porosity, thermal conductivity and mechanical strength) were determined. The analysis showed that waste foam glass functioned as an aggregate, introducing irregular voids in the matrix. The obtained composites were largely porous (>45%), with a thermal conductivity coefficient similar to that of timber (<0.2 W/m∙K). Optimum compressive strength was achieved for 10% incorporation of the waste by weight in the binder. The resulting mechanical properties suggest the suitability of the produced materials for use in thermal insulating applications where high load-bearing capacities are not required. Mechanical or chemical treatment of the waste is recommended for further exploitation of its potential in participating in the alkali activation process.

scholarly journals Potential of Green Ceramics Waste for Alkali Activated Foams

Materials ◽  
2019 ◽  
Vol 12 (21) ◽  
pp. 3563 ◽  
Author(s):  
Barbara Horvat ◽  
Vilma Ducman
Keyword(s):  
Low Cost ◽  
Alkali Activation ◽  
Activation Process ◽  
Foaming Agents ◽  
Insulating Material ◽  
X Ray ◽  
Thermal Insulating ◽  
Technical Ceramics ◽  
Body Residue ◽  
Alkali Activated

The aim of the paper is to research the influence of foaming and stabilization agents in the alkali activation process of waste green ceramics for future low cost up-cycling into lightweight porous thermal insulating material. Green waste ceramics, which is used in the present article, is a green body residue (non-successful intermediate-product) in the synthesis of technical ceramics for fuses. This residue was alkali activated with Na-water glass and NaOH in theoretically determined ratio based on data from X-ray fluorescence (XRF) and X-ray powder diffraction (XRD) that was set to maximise mechanical properties and to avoid efflorescence. Prepared mixtures were compared to alkali activated material prepared in theoretically less favourable ratios, and tested on the strength and density. Selected mixtures were further foamed with different foaming agents, that are Na-perborate (s), H2O2 (l), and Al (s), and supported by a stabilization agent, i.e., Na-dodecyl sulphate. The goal of the presented work was to prepare alkali activated foam based on green ceramics with density below 1 kg/l and compressive strength above 1 MPa.

New Thermal Insulating Material Based on Geocement

2013 ◽  
Vol 838-841 ◽  
pp. 183-187 ◽  
Author(s):  
Vít Petranek ◽  
Sergii Guzii ◽  
Pavel Krivenko ◽  
Konstantinos Sotiriadis ◽  
Anastasiia Kravchenko
Keyword(s):  
Thermal Conductivity ◽  
Heat Flow ◽  
External Heat ◽  
Great Scientist ◽  
Insulating Material ◽  
Average Temperature ◽  
Thermal Insulating ◽  
The Matrix ◽  
Birthday Anniversary ◽  
Alkali Activated

A new thermal insulating material was developed on the basis of a geocement, formulated as Na2OAl2O36SiO220H2O. Ground limestone and aluminosilicate pellets were used as fillers for its production (composition: geocement 64.29 wt. [%]; fillers 35.71 wt. [%]). This material, which is applied having a thickness of 3.0-4.5 mm, swells when it is exposed to an external heat flow of 1273 K average temperature. Swelling is due to the matrix phases and filler dehydration, which include heulandite, ussingite, sodium zeolite and other phases. As a result, a finely porous glassy aluminosilicate frame of jadeite-albite composition is formed, which is characterized by low thermal conductivity (0.09-0.175 Wm-1K-1). The developed material can be used to protect and to insulate wooden, metal and concrete surfaces from an one-sided heat source.The paper is dedicated to the great scientist of the XXI century in the field of alkali-activated cements and materials based on them, Pavlo Kryvenko, in honor of his 75thbirthday anniversary.

scholarly journals Thermoset Polymer Matrix Composites of Epoxy, Unsaturated Polyester, and Novolac Resin Embedding Construction and Demolition Wastes powder: A Comparative Study

Polymers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 737
Author(s):  
Costas Bogiatzidis ◽  
Loukas Zoumpoulakis
Keyword(s):  
Thermal Conductivity ◽  
Shear Strength ◽  
Mechanical Performance ◽  
Polymer Matrix Composites ◽  
Unsaturated Polyester ◽  
Construction And Demolition Waste ◽  
Demolition Waste ◽  
X Ray ◽  
Thermal Insulating ◽  
The Matrix

Composite materials that consisted of a polymer resin as matrix (PMCs), filled using construction and demolition (C&D) wastes powder of different grain sizing in micro-scale were manufactured and studied. Three different kinds of resins were used as the matrix for the purposes of this study. More specifically, composites made of epoxy and unsaturated polyester resins purchased from the market and phenolic resin (novolac) laboratory synthesized, were produced. The morphological and elemental analysis of these materials was performed through scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). Additionally, mechanical performance and thermal insulating efficiency of these materials were examined through bending and shear strength tests according to the three-point method and via determination of the thermal conductivity coefficient λ. C&D wastes have undergone the appropriate processing in order to prepare filling products of the required granular size in pulverized form. In this research study, construction and demolition waste-based thermosetting polymer composites were produced with flexural strength in the range 20–60 MPa, shear strength in between 1–8 MPa, and thermal conductivity coefficients in the range of 0.27–1.20 W/mK. The developed materials embedded 30–50% w/w C&D wastes, depending on the resin used as the matrix.

scholarly journals Nature Conservation Technology for Producing Slag-Foam Glass as a Structural and Thermal Insulating Material

2018 ◽  
Vol 41 ◽  
pp. 02017 ◽  
Author(s):  
Natalia Gilyazidinova ◽  
Nadezhda Rudkovskaya ◽  
Tatiana Santalova
Keyword(s):  
Foam Glass ◽  
Glass Production ◽  
Average Density ◽  
Liquid Sodium ◽  
Insulation Material ◽  
Thermal Insulating ◽  
Soluble Glass ◽  
Ferroalloy Plant ◽  
Conservation Technology ◽  
Sodium Glass

The purpose of the research is to determine the starting material composition, the conditions for its heat treatment and operation, and also the development of the recommendations on the technology of manufacturing and use of slag-foam glass as a structural and thermal insulation material for low-rise construction. Research and development of the composition and technology of ferrosilicate dust - a secondary product of the Novokuznetsk ferroalloy plant and Kemerovo chemical enterprises - slag-foam glass production, were carried out taking intoaccount the need for recycling of waste generated during the production process. The liquid sodium glass production waste is a mixture offerrosilicate dust that is not completely exhausted in the reactors and anaqueous Na2OSiO2 solution. Its density varies from 1.2 g/cm3 to 1.5 g/cm3, and the binding properties are extremely unstable, they depend on the soluble glass and water ratio in the waste. The use of this material as the basis for the production of structural and thermal insulating slag-foamglass with the stable strength index, the average density and the long-term durability is quite relevant.

GLIDCOP AL-15

Alloy Digest ◽  
1996 ◽  
Vol 45 (5) ◽  
Keyword(s):  
Thermal Conductivity ◽  
High Temperature ◽  
Aluminum Oxide ◽  
Physical Properties ◽  
High Strength ◽  
Thermal Softening ◽  
Second Phase ◽  
Temperature Performance ◽  
The Matrix ◽  
Metal Products

Abstract GlidCop AL-15 is copper strengthened by adding a second phase, aluminum oxide, to the matrix by internal oxidation. The process produces a product with resistance to thermal softening, high strength, and creep, combined with high electrical and thermal conductivity. (See also GlidCop AL-25, Alloy Digest Cu-604, June 1996, and GlidCop AL-60, Alloy Digest Cu-608, August 1996.) This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as creep. It also includes information on high temperature performance as well as forming and joining. Filing Code: CU-603. Producer or source: SCM Metal Products Inc.

Alkali-Activated Fly Ash Foams – Synthesis, Chemo-Physical Properties and Microstructure Modeling

2014 ◽  
Vol 92 ◽  
pp. 14-19 ◽  
Author(s):  
Petr Hlaváček ◽  
Vit Šmilauer ◽  
František Škvára
Keyword(s):  
Thermal Conductivity ◽  
Compressive Strength ◽  
Fly Ash ◽  
Thermal Capacity ◽  
Alkali Activation ◽  
Activation Process ◽  
Strain Diagram ◽  
Element Analysis ◽  
Aluminium Powder ◽  
One Year

Inorganic foams offer several unique properties such as low thermal conductivity, fire resistance, or UV stability. Inorganic foam specimens were synthesized from fly ash and aluminium powder through an alkali-activation process. Depending on mix proportions, bulk densities ranged between 400 and 800 kg/m3. Thermal treatment at 80°C for 12 hours accelerated curing process. Compressive strength was found in the range 4.5-9.0 MPa, flexural strength 0.6-1.7 MPa, Young's modulus 0.6-1.1 GPa, thermal conductivity 0.14-0.16 W/m/K and thermal capacity around 1100 J/kg/K. Exposing the foams to temperature 800°C led to a small decrease of compressive strength while exposure to 1100°C sintered the foam to higher strength of 13 MPa. Volumetric shrinkage 20% occurred at 1100°C without further disintegration. Residual compressive strength was determined after exposure to NaCl, HCl, Na2SO4, MgSO4, H2SO4. The highest reduction to 20% occured in both acids with pH=2 after one year of exposition. Digitized microstructures entered finite element analysis to validate a stress-strain diagram.

scholarly journals Efficient chemical stabilization of tannery wastewater pollutants in a single step process: Geopolymerization

2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Giacomo Boldrini ◽  
Caterina Sgarlata ◽  
Isabella Lancellotti ◽  
Luisa Barbieri ◽  
Marco Giorgetti ◽  
...  
Keyword(s):  
Room Temperature ◽  
Single Step ◽  
Alkali Activation ◽  
Activation Process ◽  
Complex Task ◽  
Leaching Test ◽  
The Matrix ◽  
Wastewater Pollutants ◽  
Average Compressive Strength

AbstractThe treatment of tannery wastewaters is a complex task due to the complexity of the waste: a mixture of several pollutants, both anionic and cationic as well as organic macromolecules which are very hard to treat for disposal all together. Geopolymers are a class of inorganic binders obtained by alkali activation of aluminosilicate powders at room temperature. Such activation process leads to a cement like matrix that drastically decreases mobility of several components via entrapment. This process taking place in the matrix can be hypothesized to be the in-situ formation of zeolite structures. In this work we use a metakaolin based geopolymer to tackle the problem directly in an actual industrial environment. To obtain a geopolymer, the metakaolin was mixed with 10 wt% of wastewater added with sodium hydroxide and sodium silicate as activating solutions. This process allowed a rapid consolidation at room temperature, the average compressive strength was between 14 and 43 MPa. Leaching tests performed at different aging times confirm a high immobilization efficiency close to 100%. In particular, only the 0.008 and 2.31% of Chromium and Chlorides respectively are released in the leaching test after 7 months of aging.

scholarly journals Use of Ceramic Sanitaryware as an Alternative for the Development of New Sustainable Binders

2015 ◽  
Vol 668 ◽  
pp. 172-180 ◽  
Author(s):  
Lucía Reig ◽  
M.V. Borrachero ◽  
J.M. Monzó ◽  
Holmer Savastano ◽  
Mauro M. Tashima ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Portland Cement ◽  
Sanitary Ware ◽  
Pozzolanic Activity ◽  
Raw Material ◽  
Alkali Activation ◽  
X Ray ◽  
Amorphous Phases ◽  
Ceramic Sanitary Ware ◽  
Alkali Activated

Large amounts of ceramic sanitary-ware waste are generated in both the production process and construction and demolition practices. This waste contains amorphous phases that may react with the Portlandite that originates during Portland cement hydration or with an alkali solution, leading to a low CO2-binding material. This study investigated the pozzolanic activity of ceramic sanitary-ware waste, together with its potential to form new binders by alkali activation. For this purpose, raw material was characterized by X-ray diffraction, X-ray fluorescence, particle size distribution, thermogravimetry (TGA) and scanning electron microscopy (SEM). Percentages of ceramic waste of 15 wt.% and 25 wt.%, to replace Portland cement, were used to assess the pozzolanic behavior of this material, and samples were cured at 20oC for different curing times. Alkali-activated samples, in which Ca (OH)2 was used as a source of calcium, and NaOH and sodium silicate solutions were utilized as activators, were cured for 7 days at 65oC. The microstructural evolution of the developed binders was assessed in pastes by SEM and TGA analyses, and mortars were used to evaluate the compressive strength behavior. While some strength gain was observed due to pozzolanic activity, compressive strength values within the 14-36 MPa range were obtained in the alkali-activated mortars in accordance with the activator concentration and the percentage of Ca (OH)2 addition.

Study on Performance of Alkali-Activated Flyash-Based Geopolymer Reinforced by Silica Fume and Styrene-Acrylic Emulsion

2011 ◽  
Vol 374-377 ◽  
pp. 1632-1636
Author(s):  
Ya Chao Wang ◽  
Yao Jun Zhang ◽  
Yong Xu ◽  
De Long Xu
Keyword(s):  
Fly Ash ◽  
Silica Fume ◽  
Doping Content ◽  
X Ray Diffraction ◽  
Acrylic Emulsion ◽  
X Ray ◽  
Structure Morphology ◽  
The Matrix ◽  
Compressive And Flexural Strengths ◽  
Alkali Activated

In order to improve the inherent fragility of alkali-activated fly ash-based geopolymer, the silica fume and styrene-acrylic emulsion were used to reinforce and toughen the geopolymer. The phase structure, morphology and chemical composition were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and X-ray fluorescence (XRF). The results showed that the mechanical properties of alkali-activated fly ash-based geopolymer were dramaticlly improved and the specimen with doping content of 10 wt% silica fume, 1wt% styrene-acrylic emulsion and 15wt% the alkaline excitation agent Na2SiO39H2O showed the highest compressive and flexural strengths of 42.11MPa and 5.30MPa in the ambient temperature curing 28d, respectively. SEM results indicated that doped silica fume and styrene-acrylic emulsion were embedded within the matrix of fly ash-based geopolymer. XRD results demonstrated that the mineral structures did not change obviously when silica fume and styrene-acrylic emulsion were added to the geopolymer

scholarly journals Alkaline Activation of Kaolin Group Minerals

Crystals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 268 ◽  
Author(s):  
Oliwia Biel ◽  
Piotr Rożek ◽  
Paulina Florek ◽  
Włodzimierz Mozgawa ◽  
Magdalena Król
Keyword(s):  
Sodium Hydroxide ◽  
Water Glass ◽  
Small Addition ◽  
Alkali Activation ◽  
Structural Studies ◽  
Structure And Properties ◽  
X Ray Diffraction ◽  
Bulk Materials ◽  
X Ray ◽  
Alkali Activated

Zeolites can be obtained in the process of the alkali-activation of aluminosilicate precursors. Such zeolite–geopolymer hybrid bulk materials merge the advantageous properties of both zeolites and geopolymers. In the present study, the effect of the type and concentration of an activator on the structure and properties of alkali-activated metakaolin, and metahalloysite was assessed. These two different kaolinite clays were obtained by the calcination of kaolin and halloysite, and then activated with sodium hydroxide and water glass. The phase compositions were assessed by X-ray diffraction, the microstructure was observed via scanning electron microscope, and the structural studies were conducted on the basis of the infrared spectra. The structure and properties of the obtained alkali-activated materials depend on both the type of a precursor and the type of an activator. The formation of zeolite phases was observed when the activation was carried out with sodium hydroxide alone, or with a small addition of water glass, regardless of the starting material used. The higher proportion of silicon in the activator solution does not give crystalline phases, but only an amorphous phase. Geopolymers based on metahalloysite have better compressive strength as the result of the better reactivity of metahalloysite compared to metakaolin.

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